Perturbation-evoked lateral steps in older adults: Why take two steps when one will do?

Area of Science:

• Gerontology
• Biomechanics
• Kinesiology

Background:

• Hip fractures are common in older adults, often caused by lateral falls.
• Older adults exhibit multistep responses to lateral perturbations, unlike younger adults' single sidesteps, increasing fall risk.

Purpose of the Study:

• To compare stepping characteristics and balance stability between single and multistep responses to lateral perturbation in healthy older adults.

Main Methods:

• Eighty-four older adults underwent lateral waist-pull perturbations.
• Quantified spatio-temporal stepping characteristics and balance stability.

Main Results:

• Single lateral sidesteps led to fewer steps for balance recovery compared to multistep responses.
• Single step responses demonstrated greater stability than multistep responses.
• Multistep responses showed increased center of mass velocity and reduced stability margin.

Conclusions:

• Difficulty in terminating center of mass motion or inefficient control differentiates single and multistep responses.
• Future research should explore perturbation training and hip abductor muscle conditioning to enhance compensatory stepping.